The power outage that was nearly citywide Sunday night was caused by a failed lightning arrester in the Huntsville Utilities Central substation, triggering a “domino effect” of other outages.

According to Huntsville Utilities, “Initial reports from last night indicate a lightning arrester, which is a device that protects electrical equipment in substations from surges caused by lightning or other causes, failed in the Central substation.

“Since the Central substation also feeds power to other substations, this caused a domino effect that led to additional outages in the system.

“Our crews are using the light of day to continue their inspections and determine what caused this failure.”